Draft: Additional Float value tests in Windows (#15670, #20424)

Following !7480 (which also reenabled FloatFnInverses test), added extra tests for asinh 0.0 (should be 0.0, not -0.0) etc.

Where is the key part of this patch? That is, what should reviewers look at first?

ghc\testsuite\tests\numeric\should_run\all.T adds new test file FloatValues.hs

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